DCC. l7, J. B_ MALIN HAL _ INTERNAL-COMBUSTION ENGINE Filed March 4, 1944' Nim ' 3 SheetSTSheet 1~ Dec, 17, 1946. J, B, MAUN HAL 2,412,821 INTERNAL-COMBUSTION ENGINE Filed March 4, 1944 l 3 Sheets-Sheet 2 I, ll! %/ / _ ' /// / 59 777’ /? 1477051125X5’ Dec- 17, 1946v J. B; MALIN ETAL 2,412,821 INTERNAL-COMBUSTION ENGINE Filed Match 4, 1944 E496" . a Sheets-Sheet s J0 / // ///////////// ////////9 / 24 ZKJ/VJE'CTIOIV ' L BY 1 Patented Dec. 17, 1946 2,412,821 ~ n UNITED STATES.’ PATENT oFFica ' 2,412,821 INTERNAL-COMBUSTION ENGINE Jay B. Malln, Fishkill, and William N. Fenney, New York, N. Y., assi‘Knots, by mesne assignments, to The Texas Compa a corporation of Delaware ~ , New York, N. Y., Application March 4, 1944, Serial No. 525,006 ' 3 Claims. This invention relates to an internal combus tion engine and to a method of operating such an engine. > ‘ > (01'. 123-32) taneous ignition, and knocking of the engine is not possible. ‘ y In carrying out said invention, the compressed The present invention relates to a modi?cation air within said combustion space and the locus of the internal combustion engine, and method of ‘fuel injection are moved relatively to each ' of operating that engine, wherein combustion is other in an orderly manner throughout the period independent of the spontaneous ignition quality of fuel injection to thereby impregnate the local of the fuel employed, as generically disclosed and ized portions of air at a predetermined fuel-air ' claimed'in the copending application of Everett ratio. In one embodiment speci?cally claimed in M..Barber, Serial No. 513,232, ?led December 7, l0 said application, the air is introduced into the .1943. ‘The present modi?cation is distinguished combustion space in a manner to produce a from the embodiments of the generic invention a high velocity induction air swirl within the disc which are speci?cally claimed in said application shaped combustion space, which air swirl is main Serial No. 513,232 by the injection of fuel in a ‘direction counter to the. direction of air swirl 15 tained during compression and the period of in jection, and the fuel is injected froma point lo within the cylinder combustion space, and by a cated in the cylinder wall generally tangentially critical relationship of injection ‘advance to lg of the combustion space and in the direction of nition advance and a critical positioning of the air swirl, with spark ignition occurring at a point fuel nozzle and jet with respect to the ignition close to the nozzle tip and adjacent-the cylinder . 20 wall at the side of the fuel spray. The present in In accordance with the generic invention of device. _ - ' ' ' \said application Serial No. 513,232, air unmixed with fuel, or air containing insu?icient fuel to vention involves a modi?cation .of this form em ploying high velocity induction air swirl. ' In accordance with the present invention, the ' support combustion, is introduced into the disc-, shaped combustion space of the engine cylinder 25 fuel is injected in a Jet extending along a chord of the combustion space moving across the swirl and compressed on the compression stroke, fuel is injected into said vcompressed air during the latter part of the compression stroke under con ditions such that at least‘a part rapidly vaporizes ing air from a point adjacent the periphery of the combustion space and counter to the direction ‘ of air swirl. A spark of ignitible intensity is pro ‘ and forms combustible fuel vapor-air mixture 30 vided in the combustion space about 15-32 crank angle degrees after the beginning of fuel injection, with, only a short travel from the point of injec tion, this combustible mixture formed from the ?rst increment of injected fuel is spark ignited substantially as soon as formed and before suf ' ?cient fuel has been injected to disseminate widely withinthe combustion space, whereby only a lo ‘ lcalized patch of combustible mixture exists within , the combustion space at the time of ignition and the establishment of a ?ame front, and then the . ' said spark being positioned slightly on the air down-stream side 01' said fuel jet to ignite the combustible fuel vapor-air mixture formed from the first increment of injected fuel substantially as soon as the swirling air has blown or diverted the same into contact with the point of ignition. ' It is important that the location and design of the means for injecting fuel be such that the fuel _ injection of fuel is continued during the balance '40 may be injected into the combustion chamber in Y a direction against the‘air swirl. and on the'air ofthe injection period into a narrow zone or upstream side of the ignition means adjacent to ‘ zones of. the combustion chamber immediately in but not impinging on such means. Also, the in a‘ advance of the flame front, whereby additional jection should be in a direction suchv that the I quantities of, combustible fuel vapor-air mixture swirling air tends to blow the injected fuel. or are progressively formed, ignited. by the ?ame 45 rather a resulting mixture of fuel and air, in con- ' and burned substantially as rapidly as produced. The ‘net result is that any combustible fuel vapor ‘airf mixture undergoing combustion within the 1 cylinder is so rapidly consumed after formation that it is cushioned by a mass of incombustible 50 vgas,_including ,air, products ‘of combustion and in ‘combustibly rich mixture. Consequently, there is ellminated the formation of highly compressed and ,heated end’ gases consisting of combustible _fuel_vapor-air mixture which can undergo spon tact with the ignition means. In other words, the fuel should be injected sothat it enters the planes in which the air is swirling that pass through the _ ignition means. Accordingly. where a disc-shaped combustion chamber is provided and the ignition means is disposed in the cylinder head, the fuel may be injected from the side of the cylinder in a di rection which is toward the air upstream side of the ignition means and also is directed upwardly 2,412,821 toward the cylinder head. In this way the fuel is placed in a position to be blown in the direction of the ignition means. 4 Figure 1, looking up at the top of theengine cylinder; however, with the injection mechanism removed; Figure 3 is an enlarged, detailed sectional view As distinguished from the speci?c embodiment of the inner end of an adapter employed in con~ disclosed and claimed in said application Serial nection with the injection mechanism, the section No; 513,232, wherein the direction and intensity taken through the middle of the opening ' of the fuel jet introduced in the direction of' air > being in the adapter; i. e., on line 3-3 of Figure 4; swirl is s'uflicient to carry that jet substantially to Figure 4 is a diagrammatic illustration of the vthe point of ignition in about 4-10'crank angle manner in which the adapter is placed in the side 10 degrees after the start of injection, the present of the cylinder wall; ' invention operates on the principle of utilizing Figure 5 is a diagrammatic view looking up at the swirling air to pick up and divert, vaporized the engine cylinder shown’ in the preceding ?g fuel from the edges of the jet, and'carry the re ures, illustrating the conditions of air swirl and sulting combustible fuel vapor-air mixture to the’ fuel injection within the combustion chamber; point of ignition. While a close positioning ‘of the Figure 6 is a diagrammatic side view of this point of ignition with respect to the point of in cylinder, further illustrating the conditions with jection is of critical importance, therelationship in the cylinder; . of the jet itself to the point of ignition is quite Figure '7 is a diagrammatic sectional view look- v different from the previous embodiment and the time at which a spark of ignitible intensity must 20 ing towards the head of another engine cylinder ; . in which the point of injection and spark plug be present after the start of injection is longer occupy different relative positions; and, and less critical than in said previous embodi Figure 8 is a diagrammatic sectional view of the ment. In one speci?c application of the present engine cylinder shown in Figure 7, the view be invention, the jet is directed along a_chord of the combustion space counter to the direction of 25 ing a vertical section through the cylinder look ing in the‘ direction of the point of injection and air swirl, so that the center line of the jet makes an angle of about 30° with the radius of the com bustion space passing through the point of in ' jection when viewed in a horizontal plane, and , spark plug. , v Referring to Figures 1 and 2, the engine cylinder is shown at l0, having the usual water jacket II. the point of ignition is located substantially on 30 Disposed in the cylinder is a piston I2 having a said radius less than half way from the point of injection to the center of the combustion space. In another speci?c embodiment, wherein the fuel is injected along a chord of the combustion space connecting rod l3 which runs to the usual crank, shaft, not shown. The cylinder head is equipped with an intake port controlled by a poppet intake valve M. This port communicates with a con in substantially the same angular relationship and 35 ventional air-intake pipe or manifold , (not shown). As shown in Figure 2, the valve I4 is also at an upwardly inclined angle toward the provided ‘with a shroud'l6 which covers 180 de cylinder head, the point of ignition is located ad grees of ' the valve opening. ' _ jacent the cylinder wall substantially directly It will be seen that when this valve is opened, It is pointed out that, in adapting conventional 40 the direction of air ?ow through the valve is tan gential to a circle having its center at the axis engines to the present method of operation with of the cylinder, which is effective to impart a non-knocking combustion, di?iculties sometimes swirling movement of high velocity to the air ' arise in providing space in the cylinder wall for introduced into the combustion space in thedi- , the mounting of the fuel injection nozzle and the spark plug in proper-relationship to secure satis 45 rection of the arrow IS. The cylinder is ‘also equipped with an exhaust p011; which is controlled ,. factory operation with the fuel injected generally tangentially of the combustion space in the di by valve a poppet leads to valve a conventional IT. The portexhaust controlled valve by pipe this . , above the point of fuel injection. rection of air swirl. Also, in some cases, it is de- or manifold (not shown). It will be understood sirable to avoid the critically short relationship between the time of the beginning of fuel injec 60 that the valves l4 and 11 may be actuated in the. ' customary manner by suitable cams carriedby a tion and the time of spark ignition required with that embodiment. It is accordingly seen to be an conventional valve cam shaft. . As shown, a disc-shaped combustion spa'e?'a, object of the present invention to overcome these is formed by the head and wall of the engine cyl di?icultiesand to provide satisfactory engine con structions, and methods of operating such engines, 55 inder and the head of the piston.‘ While the pis ton and cylinder head are shown in Figure ‘1 as wherein the fuel may be injected in a direction being ?at, either or both may be dished or counter to the direction of air swirl. crowned, as discussed above. Thus, it is to be un From the foregoing discussion, it will be under derstood that the term "disc-shaped” is used in a stood that, provided the conditions described above are maintained, the speci?c arrangement 60 broad ‘sense as meaning a combustion space which is generally circular in cross section, but which of mechanical elements required to create these may have various con?gurations in vertical sec conditions may be varied. However, in order that _ tion due to dishing or crowning of the cylinder the invention may be understood more fully, there > will be described, in connection with the accom~> head or piston. » ' _ The cylinder head is provided with an opening panying drawings, forms of modi?ed engines in 65 2| in which is disposed a threaded reducing mem which operation with a low octane fuel at high ber 22, having an opening 23 for receiving a spark compression ratios and without knock has been plug 24. It will be noted that by this arrange accomplished. In the drawings: . Figure 1 15a view partly in section on the line ment, the electrodes of the spark plug extend ’ l---lv of Figure 2 of the cylinder of ‘an engine 70 somewhat into the combustion space. The cylin der is also provided in its. side with a threaded equipped in accordance with the present inven radial bore 26, the center of which is in line with 1 tion. In this ?gure, the fuel system employed and thecenter of spark plug 24. As shown‘ inFigure . . the injector are more or less diagrammatically il 1, there is disposed an adapter 21 in threaded en Figure 2 is a sectional view on the line 2--2 of 76 gagement with bore 26. The adapter accom lustrated; } . . , ‘ simian " ~' plishestwo' functionsr'it encloses and supports . ' . _ ' ' ber, by-pass port, check valve, and a plunger pro-:- 7 j " ' up' and directing the-spray from the injector noz vided with a scroll or helix on its surface, whereby " ,zle. _ The injector 28 is, of the conventional type in which theorifice opening is normally held 5 tle. The fuel under high pressure is introduced ‘closed by means of a spring-pressed nozzle pin ‘through a suitable conduit 29 into a chamber sur-‘ ' b which is, provided with an intake port, fuel cham+ . anI injector‘ II and‘ provides means for breaking ‘ the amount of fuel can be controlled by rotation; V of the plunger. Pumps of this type are well; known in the art and are described, forexample, ‘ at pages 14 and 214 of the Diesel Engine Catalog, ' Diesel Engine; Inc., New York, 1941, volume ‘six. ‘ ‘ rounding the conical end of the nozzle pintle. ' A port-‘controlled plunger pump permits variation When the pressure on the fuel is su?iciently high, . in the amount of fuel injected so as to accomplish the nozzle pintle is raised and fuel issues in spray full or part load operation. Also, the pump ef form from the opening. ‘Since injectors of this fects sharp termination of the feed of fuel under, type are well-known in the art, in Figure 1 only the-inner end of the injector-is shown in detail; ' pressure su?lcient to operate the fuel injector.’ '_ ‘ As shown in Figure‘ 1, the pump plunger “is ~ _ Thus, the fuel enters through the conduit 2!, Operated by a suitable cam _44 which may be in- j- . g a ?ows into a fuel chamber Ii at‘ a pressure suf ,. terconnected with the crank shaft of the engine ‘ * ‘ ?ciently high to raise a nozzle pintle-ll' and per in‘conventional manner. The fuel under a‘. 1.11811 mit the flow of the fuel‘ through orifice opening 88. pressure which may be of thev order of 500 to 4,000 ' The inner end of the adapter 21- utilized in this pounds per square inch is forced through line 46 embodiment .of the invention will be described 20 leading into conduit 29 in injector 28, as pre- 7 ' more in detail. It is provided with an opening I4 viously7 described. The fuel in ?owing through which leads from the orifice opening of the in line 48 may be heated if desired, and there'is . jectorto the. interior of the cylinder. Referring particularly to Figure 3, it will'be seen that the 1 ‘shown for this purpose a-heatin'g coil 41. The angle of the opening inthe plane on which this 25 fuel supplied under the high pressure during the? period of injectioni'lows into fuel chamber 3i and ?gure is drawn with the axis of‘ the adapter is the angleA, which in this case is .40- degrees. ' the force resulting from the pressure on .the fuel lifts nozzle pintle 42 and permits a jet of fuel to ' Also, it will be seen'that the angle formed be pass through ori?ce. 33. The fuel enters opening f "tween the sides of the opening is angle 3, which in this case is 10 degrees. .As shown in Figure 4, > 84 in the inner end of adapter 21, is broken up- '. into a fine spray and injected into the swirling and also, to some extent, in Figure 1, the adapter 3"' air. as described. opening is arranged, whenin place, so that the The first increments of injected fuel form a center line of the opening forms an‘ angle‘ C combustible mixture with the'swirling air, and a (which in this case iii-45 degrees). with the hori zontal. Accordingly. the adapter directs the fuel 35 this mixture is blown into contact with the elec trodes of spark plug 24. At this time or shortly spray upwardly and to the right in Figure l - thereafter, a spark of igniting intensity is passed (downwardly and at an angle in Figure 2). This between the electrodes of spark plug 24 and the mayalsobeseenbyreferencetoFigures5and8, combustible‘ mixture is ignited.'- During the re in which the direction of the spray is perhaps shown more clearly. In these two figures, the so mainder of the period of injection, the remainder ' of the fuel is injected into the swirling air and' ' spray is shown as it would appear under normal is promptly burned in the existing ?ame front. atmospheric conditions and in the absence of air It will be noted that the fuel is injected into the swirl._ Fuel injection mechanism‘ including an swirling air before the flame front, which tends adapter, and the adapter per se, are disclosed and to advance towards the point of injection. It is claimed in the copending application of Jay 13. ... probable, however, due to the swirling air, that _ .Malin, Serial No. 515,234, ?led December 22, 1943. - the ?ame front remains substantially stationary While not speci?cally illustrated in the drawings, in relation to the cylinder walls. ‘ ' it will beam that the center line of the adapter ‘Another arrangement which has been found opening forms, in a horizontal plane containing to give knockdree operation even at high com--v the center line of the injector, a projected angle . of about 30'degrees with the center line of the 5o pression ratios and charge densities is shown in j ’ Figures 7 and 8. As shown in these figures the injector. Thus, the fuel spray is directed about 30 degrees from the radial direction towards the edge sparkofplug the is combustion disposed in space the and cylinder the point wall; at of the, in- * I air upstream side of the combustion-space. Un jection (injection nozzle) is located just below; '_ doubtedly, under actual conditions of operation as the plug. The fuel is injected against the direc where higher pressures and temperatures prevail tion of air swirl on the air up-stream side of ‘ and theeifect of air swirl is felt, the actual spray the plug and the combustible mixtures formed be form is somewhat different from that shown. As tween the fuel and the air are blown into contact shown in Figures 5 and 6, the spray is such that‘ the electrodes of the spark plug. "It will ' under non-operating conditions,‘ the spray im on with be noted that the fuel spray is at least partly di-, pinges upon the cylinder head over an area on rected towards the top of the cylinder, and this the air upstream side of the spark plug. is preferred practice. Refen'ing again to Figure 1, the operation of It will be understood that'in' order to accom - the engine illustrated will be described more in plish effective operation of the engine. the sev 65 eral factors affecting such operation should be ' ' 0n the suction stroke of. the engine, air is in coordinated. Considering ?rst the locations of troduced through intake valve l4 and is caused ' ' the point of injection and the spark plug, these to swirl by means of the shroud it, as previously ‘ detail. . v . described. At a selected point near the top of . fuel should with be selected the swirling so that airsu?lcient is permitted admixture'of‘ prior to ' piston travel, the injection of the fuel into the swirling air is begun. The fuel system diagram 70 the time when any considerable amount of fuel matically illustrated in Figure 1 includes a fuel storage vessel 38 from which the fuel is pumped ' through line 38 to a pump 42. The pump shown reaches the spark plug, but not so far away from} the zone of injection as to permit extensive dis semination of fuel throughout the combustion space before ignition, While the particular ar is a conventional port-controlled‘ plunger pump 75 rangein'ents shown‘ in the drawings have been ~ ' 2,412,821 . 7 ' ' 8 . in the drawings. While a 180 degree shroud is shown, it is believed that shrouds covering more or less of the valve opening would produce the desired swirl. The rate of swirl should be such found to be satisfactory, in cases where‘ other mechanical arrangements are possible without interfering with valve operation, the spark plug‘ may be displaced somewhat from the positions shown. ,It should also be pointed out at this time that the arrangements shown were em-' ployed in a cylinder having a bore diameter of 31/4 inches, and in utilizing a cylinder with a larger bore, greater variation in the position of the spark plug would be possible. It is to be understood that the spray pattern, fuel intensity of the jet'and velocity of the swirling air are altered, and correlated for the different spacings as to produce about six revolutions or more of the air for each engine revolution. It ispreferred . also to control the duration of injection so that the injection of fuel takes place during one revo lution of air, since in this way the air is uniformly V 10 impregnated with fuel. An important feature of the present invention is the proper synchronization of the spark ad' vance with the injection advance to secure igni tion of the ?rst increment of' injected fuel sub stantially as soon as that fuel has mixed with the ' . .. of the spark plug and point of injection, in order toobtain the desired knock-free operation.~ ‘~ qThe ‘point in the compression stroke at which ‘ air to form a combustible fuel vapor-air mixture, thednjection ofv fuel is begun may be varied; for \and that mixture has been blown into contact with the electrodes of the spark plug. Proper syn . wexample,» it may be as much as '75 degrees before - chronization requires that a spark ofiigniting in tensity be available at the time this'L?rst-formed portion of the combustible fuel vapor-air mixture reaches the spark plug, or very shortly there ‘;.,;:t,()p&dea,d center, and for maximum power, if- sub ;stantially all’ of the air within the combustion space isto be consumed, it may be about 50 to 40 degrees before this point. Where thepower re , qui-red-is'less, the beginning of fuel injection‘may be at or- shortly after top dead center, or, for the smaller power. requirements, the injection may stillubeinitiated prior to top dead center and may be cut off so that only that portion of air after. ‘ While the present invention can be operated‘ with a substantially instantaneous spark at the ' plug electrodes, this requires a critical coordina tion of the'spark advance with. the injection ad' For example, in the construction shown 1 is consumed which is necessary to supply the ~ power required. In generalI itmay be stated that ' vance. in Figures 1 to‘ 6, work done using ignition sys tems producing sparks of appreciable duration the injection of fuel should preferably be started ' showed, that knock-free operation was possible, provided a spark of igniting intensity was present within about 15 to 32 degrees after the start of substantially before top dead center, for example‘, 75 to 30 degrees before this point, and should preferably be ended before or slightly after top injection. If “the spark occurs too soon and is not . dead center. ‘ The amount of fuel'that may be injected in a 35 maintained, by the time a‘ combustible fuel-air mixture is formed there is present no means for cycle is, of course, dependent upon the weight of igniting-the mixture and missing occurs. On the .air available for admixture therewith to form other hand, when the spark occurs too late, op portunity is afforded for the dissemination of andpressure‘at which the air is introduced into ‘to fuel widely throughout the combustion space, making possible the formation of a combustible the engine cylinder. For example, under boost combustible mixtures. The weight of air avail able, in turn, 'isdependent upon the temperature ~ . . pressures,qmore air will be available than when xthe air is introducedat atmospheric pressure.v Also, the amount of fuel that'may be injected and burned eifectivelyis'dependent upon the air ~ .‘available in the zone;of injection or impregna . - tion, and'this is affected by the velocity of air - ,swirl. Normally, the. rate of fuel injection should be such as to give a fuel-air ratio. in the impreg nated zone of around 0.06 for light and inter qmediate" loads, unto the point where substan end gas and permitting knock. Although where a short or instantaneous spark is employed, careful coordination between injec = tion advance and spark advance is necessary, it has been found that the conventional magneto or coil ignition systems have a spark duration of about -5 to 30 crank angle degrees at an engine speed of 1800 _R. P. M. For example, in the con-. 60 struction shown in Figures 1 to 6, and employing v‘an ignition circuit of the magneto type having a tially all of therair within the combustion space I s;.~,¢consumed.,,-To further increase the power ' ; produced on each cycle for maximum loads, the ,uelrate maybe increased for ‘a given velocity of _. swirling air so as to uniformly impregnate that airat a- fuel-airratio up to about 0.08 or above. ; It will thus ‘be seen that the duration of injection and rate of injection are dependent factors which _'-sparkv duration of about 7 crank angle degrees with a plugv gap of 0.040 inch and increasing toa ; spark duration of about 28 crank angle degrees 55. with a plug gap 0.010 inch, the engine operated ‘ satisfactorily with the following setting of spark 'advance,»using a 60° injection advance and an in jection period of about 36° throughout the runs. ‘ The runs were carried out with an overall fuel-air '- : _.th_em'se1ves are dependent upon the fuel-air ratio 60 ratio of about 0.1. With a spark duration of 7 a in; the. impregnated zone and the overall fuel-air degrees, satisfactory operation occurred with an ignition advance of about 33 to 28° B. T. 0.; and . ratio desired. While. in view of these facts no with a spark duration of 28>degrees, satisfactory . de?niteduration for injection may be set, it may be stated in general that where the overall fuel air ratio varies from 0.06 to 0.08 and the begin ,ning of injection varies from 60° to 40° B. T. C., operation occurred with an ‘ignition advance of 05 about 45 to 28° B. T. C. _ It will be obvious that the foregoing discussion is presented primarily for the purpose of disclos - the duration may be of the order of 35 to 80 crank angle degrees. 7 ing ways .in which the operation of the engine may be varied, and is not intended to indicate that . As previously indicated, a high velocity of swirl should be imparted. to the air introduced into the 70 'only the magneto type of ignition system is suit combustion space. The inventionis not limited v able or that the factors considered would be varied in an actual operating engine. For example, con to any particular means of causing this swirl and ventional ignition circuits of the coil and breaker such means are well-known in the art; however, type may be used. It may be pointed out here ‘ theuse of a shrouded intake valve has been found to be'satisfactory in an engine of the type shown 75 that experience inns indicated that a relatively, ~ amass: 9 > .10 . high current spark is'preferable. Also, a continu ous spark of longer duration. for example, a spark there may be mentioned gasoline of low or high ' ‘octane value, kerosene, Diesel fuels, methyl alco such as is used in fuel burner systems, may be employed and may be left on during the entire period of injection or may be cut o? after being hol, light lubricating oils, butane, etc. It is im portant, however, that the fuel boil over such a range that at least a portion of the fuel is'vapor on for a selected portion of the injection period. ized in the combustion space under the condi tions existing therein at the time of injection. By preheating the fuel. liquid fuels boiling over Where "spark ignition” and similar expressions appear in the description and claims, it is to be understood that these expressions include the above types or similar types of ignition systems 10 for igniting the fuel-air mixture. -, As pointed out above, the fuel jet is preferably directed towards the cylinder head at a rate which is believed to. cause the fuel to impinge on the ' . ized and/or mixed with swirling air at a relatively ' Obviously many modi?cations and variations ‘of the invention, as hereinbefore set forth, may be made without departing from‘the spirit and scope thereof, and therefore only such limita ' tions'should be imposed as are indicated in‘ the inner surface of the cylinder head. It‘ is believed 15 that the fuel which so impinges may'remain on the surface for a time, and that this fuel is vapor an elevated range may be used. appended claims. , We claim: . 1. In a spark-ignition fuel-injection intemal ' combustion engine of the character described slow rate, thus permitting injection of a substan having a cylinder with a cylinder head, .a piston, tial amount of fuel before ignition and yet avoid 20 reciprocatingly mounted therein, said parts form ing dissemination of the fuel widely in the com ing- aidisc-shaped combustion space, meansfor bustion space. .' . _ producing high velocity induction air swirl with The engine of the present invention may be in said combustion space, means for injecting fuel operated on a cycle which approximates the theo into the swirling air toward the latter part of retical Otto cycle, a cycle which approximates the compression stroke ofv the piston, means for the theoretical Diesel cycle, or a cycle which is more or less midway between the two. In a given spark igniting the first increment of‘injected engine, the cycle employed is primarily depend . fuel substantially as soon as combustible fuel va cycle approaching combustion at constant vol stantially as rapidly as formed. The modi?ca tion wherein the fuel injection means comprises por-air mixture is formed therefrom to establish ent upon the fuel injection rate and the point .where injection is begun. In view of the inher 30 a traveling ?ame front, and means for control ling the rate and duration of fuel injection after ently higher cycle efficiency of the Otto cycle, ignition to successively form additional quantities as compared to the Diesel cycle at the same com of combustible fuel vapor-air mixture immedi pression ratios, it is generally preferred to oper ately in advance of the traveling ?ame front and ate the engine of the present invention on a cycle which are ignited by the flame and burned sub- ' approaching the theoretical Otto cycle; i. e., a 35 ume. a nozzle positioned in the cylinder wall and con Inasmuch as the‘ limitations with respect to, structed to direct a fuel jet from a locus of fuel knock- are eliminated in the present invention, it is preferred to operate the engine at a high com 40 injection at the periphery across a chord ,of the combustion space counter to the direction of air pression ratio.v Thus, it is generally preferred ' swirland upwardly inclined toward the cylinder to operate the engine on the Otto cycle at a com head, and the spark ignition means comprises pression ratio of about 9:1 to 10:1 to obtain the a spark plug having electrodes positioned within inherent increase in the cycle efficiency result the combustion space at a point above the hori ing from the higher compression ratio, while, at 45 zontal plane of the locus of fuel injection and the same time, avoiding the necessary increase in slightly on the air down-stream side of the fuel cost, size, and weight of the engine that is in jet, said point of spark ignition and said locus volved in Diesel engine construction for opera of fuel injection lying in a vertical plane con tion at compression ratios at about 14:1 to 16:1. taining a radius of said combustion space. While the invention has been described above 2. An internal 'combustion engine according as applied to four-cycle operation, it is to be un 60 to claim 1 wherein the spark'plugelectrodes are derstood that the invention is also applicable to located adjacent the cylinder wall substantially two-cycle operation; in fact, the invention lends directly above the‘locus of fuel injection. A itself particularly well to two-cycle operation be- \ 3. An internal combustion engine according to cause there is no necessity for preforming the claim 1, wherein the fuel injection is constructed fuel mixture, and this enables the suction stroke to direct the jet so that the center line of the jet of four-cycle operation to be easily eliminated. makes an angle of about 30° with the radius of As previously discussed, a principal advantage the combustion space passing through the point of the engine of the invention results from the of injection when viewed in a horizontal plane, “ fact that satisfactory operation at high com 60 and the spark ,plug electrodes are positioned sub pression ratiosand charge densities and with low stantially on said radius less than half way from octane fuels may be obtained. Thus, the inven-. the point of injection to the center of the com tion includes the use of various normally liquid bustion space. . ‘ and normally gaseous fuels of both low and high JAY B. MALIN. octane values. As examples of suitable- fuels, 65 WILLIAM N. FENNEY.